Oil burner



May 2, 1939.

H. E. NELSON OIL BURNER Filed Oct. 30, 1936 INVENTOR. [/YELS /Y HENRY Maw/1 TTORNEYS.

lllllll I Patented May 2, 1939 UNITED STATES PATENT OFFICE 2 Claims.

This invention relates to improvements in oil burners, and it has reference more particularly to burners for use in the ordinary types of residence heating furnaces, heaters or cook stoves,

and which are of that type wherein the fue. oil is delivered to the burner by gravity flow under float control as differentiated from that kind using pressure feed.

It is the principal object of this invention to provide an improved burner of the type above stated by an arrangement of parts that insures an exceedingly economical use of oil and a complete combustion of the fuel; also, to provide a construction that gives easy accessibility for cleaning when such is desired or necessary.

A still further object of this invention resides in the details whereby the air entering the burner for the initial combustion of the fuel is caused to impart a whirling motion to the gases of combustion within the burner, thereby to facilitate and to insure adequate and complete mixing and burning with a better distribution of heat.

Other objects of the invention reside in the details of construction and combination of parts,

35 and in the mode of operation, as will hereinafter be fully described.

In accomplishing these and other objects of the invention, I have provided the improved details of construction, the preferred forms of which m are illustrated in the accompanying drawing,

wherein- Fig. 1 is a side view of a conventional type of residence furnace that is equipped with an oil burner embodied by the present invention; the

35 side wall of the furnace being broken away for better illustrating the disposition of the burner.

Fig. 2 is a central, vertical cross section of the burner.

Fig. 3 is a horizontal sectional detail, taken on the line 3-3 of Fig. 2.

Fig. 4 is a sectional detail on the line 4-4 in Fig. 2.

Referring more in detail to the drawing I designates what may be a furnace of a conventional type as now generally used in residence heating, and in which a burner embodied by the present invention, and designated in its entirety by reference numeral 2, is installed.

The furnace l comprises an outer shell or hous- 50 ing 3, enclosing the furnace proper, which comprises a fire bowl 4 and a lower' housing 5 which forms a compartment 6, which is separate from the combustion chamber that is formed within the fire bowl. The combustion chamber that is 5:, formed within the bowl 4 and the lower compartment-B are divided by a horizontal wall 1 having a central opening 8 of circular form within which the upper end of the burner is contained.

The burner comprises a housing ID in the form of an inverted, truncated cone. About the outer edge of the upper end of this housing is a laterally extending, peripheral flange l2, which rests upon the wall partition 1 about the periphcry of the opening 8 with the lower end of the housing depending into the lower compartment 6 of the furnace. About the base of the flange l2; that is, along the line of the junction of the flange l2 with the body of the housing, are arouate slots I3 opening therethrough to provide for an inflow of air upwardly into the combustion chamber of the bowl 4, thus to expedite combustion. A flat, annular member l5 fits within an upstanding rim flange l5 of the flange l2, and this annular member somewhat overlaps the slots l3, as will be observed by reference to Fig. 2, thus to confine the annular passage to a narrow slit I1 and the inner edge of this ring or annular member I5 is beveled inwardly, as at l8, to act as a deflecting surface whereby the infiowing air is directed toward the central axis of the combustion chamber.

Suspended from the partition 1, and enclosing, the lower end portion of the housing It! therein, is a pan-like housing 20. This is of circular form and has vertical side walls spaced outwardly from the housing l0 to provide anannular passage 22 about the latter. The upper end of the housing 20 is open and there is a lateral, peripheral flange 25 about the upper end, through which bolts 26 are extended to support the hous- 3 ing 20, with its base or bottom wall 20a held tightly against the lower end of the housing Ill. The bolts 26 extend upwardly through the horizontal wall 1 near the periphery of the opening l8, and also through the flange I2 and the ring l5, and have nuts 28 threaded onto their upper ends to hold the parts in assembled relationship. Centrally of the base of the pan-like housing 22 is a depression 30 of a diameter slightly less than the diameter of the lowerend of the housing l0, and coaxial of this depression 30, and also coaxial of the pan 20 is a cylindrical flue 35, open at upper and lower ends andforming an air inlet passageway 36 for supplying air to the combustion chamber. Resting upon the upper end of the flue is a housing 3'! of inverted, truncated, conical form, that extends just slightly higher than the housing Ill.

The housing 31 is'hollow and opens at its lower end into the upper end of the flue 35. At its upper end it is covered by a flat plate or lid 38, which is fixedly supported on bosses 39, integral with the housing 31 in a manner to provide an encircling slot 40 about the periphery of the housing 31, through which air may flow into the combustion chamber. In Fig. 2, it has been indicated by use of arrows, that outside air enters the lower end of the flue, flows upwardly therethrough into the housing 31 and then outwardly through the circumferential slit 40. It will also be observed that outside air enters the upper, open end of the housing and flows downwardly in the annular passage 22, and then inwardly through a plurality of slots or channels 42 that are cut through the lower end portion of the housing It. The air entering through these passages 42 then flows'upwardly between the housings l0 and 31 to aid in the combustion of the fuel gases produced as later described in the annular space. Outside air is admitted through the passages l l to facilitate combustion adjacent the top surface of the burner.

An annular trough is supported within the depression 30 and about the flue .35. The means of support comprises a peripheral flange 45a. on the trough that rests upon the bottom wall of the housing 20 about the periphery of the depression 30. Cut through the bottom of the trough are a number of ports or slots 46 through which fuel oil admitted into the depression 30 may rise into the trough. Fuel oil is supplied to the depression or reservoir 30 through a supply pipe 44 that leads'thereto, through a suitable float housing 48; that latter containing a float of any suitable character that operates to maintain the oil in the trough at a predetermined level. It is preferred also that the trough shall contain suitable wicking 49 to facilitate igniting and burning of the fuel oil in the trough.

It will be observed, more particularly by reference to Fig. 3, that the slots 42, which are cut through the lower end portion of the housing III, are not radial but are symmetrically angularly disposed relative to the axis of the burner so that incoming air will be directed tangentially of the outside of flue 35, thereby to create a whirling action of gases about the axis of the burner within the annular space between the housings l0 wardly between the housings Ill and 31.

as the burner becomes thoroughly heated, a.

and 31. This whirling action of the gases of combustion effects a better. mixing of air and gas, with a more complete combustion. Fig. 3 also shows the supply pipe connected with the float by an arrangement whereby removal of a closure cap 50 will give direct access through the pipe 44 for cleaning it out should this be necessary.

Assuming the burner to be so constructed, its use is as follows:

To initially start the fire, the float control, indicated at 52, is adjusted so that fuel oil will be supplied to the trough 45 to a definite predetermined level. Then the cone-shaped housing 31 is lifted out of the burner and a crumpled piece of paper or the like is placed inside the housing In and ignited. This incidentally causes the oil in the trough tobe ignited. When the oil is burning freely, the housing 31 is replaced in the position shown. This creates a strong draft up- As soon ready combustion of gases takes place and the burning oil is caused to quickly gasify with the result that the flame of combustion takes place adjacent the top surface of the burner where the air, entering through the slots l1 and 40, comes into intimate contact with the gases. Air inflowing through the flue 35 keeps the base of the burner cool, and thus there is no probability of gas being created below the trough.

It is preferred that a pan, as at 60, be supported beneath the lower wall of the depression 30 in spaced relation thereto so that all air entering the flue 35 will be caused to intimately contact the bottom surface of the depression, thus to keep this part of the equipment cool.

As here shown, the pan is hinged at one side by a hinge pin 62, and at its other edge is equipped, as shown in Fig. 4, with a yieldable clamp or clip 63 adapted to supportingly engage with pipe 44.

It is apparent that by lowering the oil level in the trough, or by cutting down the rate of supply, the flame will be reduced accordingly.

. The device as shown provides for easy and ready assembly of parts, and ready disassembly when this is desired. The device is exceptionally efliclent in use by reason of the provision of air passages and slots, and by reason of the fact that the heat produced in the burner will cause the fuel to gaslfy readily and thus mix easily with the intaken air.

Such burners may be made in various sizes and designs to accommodate various kinds of stoves or furnaces.

Having thus described my invention, what I claim as new therein and desire to secure by Letters Patent is- 1. In a furnace having a closed fire box with a bottom wall provided with an opening, an oil burner fitted in said opening and depending below said wall; said burner comprising a pan-like housing formed with an annular depression centrally in the bottom wall for a supply of fuel oil and having a central flue open at its lower end for inflow of outside air and open at its upper end; two spaced housings of inverted, conical form disposed centrally within the pan and providing an intermediate combustion space of substantial length and without flare, open at its lower end to the'annular depression and open at its upper end intd'the fire box; the inner housing being hollow and-communicating at its lower end with the flue, a cover plate applied to the upper end of the inner housing and providing an air inlet slot about its periphery for inflow of outside air to the firebox at the upper end of the said combustion space; said outside housing being spaced inwardly from the side walls of the pan and provided about its lower edge with air inlet ports ofrelatively large area into the lower end of the combustion space and at its upper edge with air inlet ports of relative small area opening into the upper end of the combustion passage.

2. The combination with a fire box, of an oil burner comprising a pan-like housing formed with a central depression for a supply of fuel oil, and a central flue for inflow of fresh air to the fire box, meansfor controlling flow of oil from a source of supply into said depression, housings disposed in said pan in spaced relation to provide an intermediate combustion space; said space being open at its lower end to said pan depres sion and open at its upper end into the fire box; a trough disposed in the depression and having ports for inflow of oil, wicking in said trough and an air deflecting pan suspended below the pan-like housing and whereby outside air antering the flue is caused to impinge the base of the oil depression to keep it cool.

. HENRY E. NELSON. 

